Circuit element construction



Feb. 21, 1961 w. T. SUTTON, JR

CIRCUIT ELEMENT CONSTRUCTION Fild June 25, 1958 INVENTOR M24 75/? Z Q/rmyu? BY W rw/J ATTORNEY.

2,972,713 CIRCUIT ELEMENT CONSTRUCTION Walter T. Sutton, Jr., Lexington, Ky., assignor to Essex Electronics, Berkeley Heights, N.J., a corporation of New Jersey Filed June 25, 1958, Ser. No. 744,463

21 Claims. (Cl. 323-74) My invention relates to an improved electrical circuitelement construction, rendering the same particularly useful in the automatic assembly of suchcircuit elements into circuits, as into printed circuits. This application is closely related in its application to the coil and trans former structures disclosed in copending Goldsmith application, Serial No. 626,175, filed December 4, 1956, now Patent No. 2,836,805.

It is an object of the invention to provide an improved construction of the character indicated.

' It is another object to provide an improved electrical circuit-element construction which lends itself with equal facility to the fabrication of capacitors or resistors.

It is a further object to achieve the above objects with a structure which lends itself to combination with coil elements in the same unitstructure.

It is a specific object to achieve the above objects with a construction in which the internal parts of the component electrical elements are themselves the mounting prongs, of strength adequate to proivde the substantial mounting support for the entire circuit-element combination.

It is in general an object to meet the above objects with an extremely rugged and simple device which can achieve or exceed the electrical performance of previous constructions, andwhich may be so rugged and permanent as to'constitute a trouble-free component for the life of the circuit in which it is embodied.

Other objects and various further features of novelty and invention will be pointed out or will occur to those skilled in the art from a reading of the following specification, taken in'conjunction with the accompanying drawings. In said drawings, which show, for illustrative purposes only, preferred forms of the invention: 1 Fig. l is a vertical sectional view of a circuit-element assembly embodying features of the invention;

Fig. 2 is an exploded view in perspective illustrating internal parts of the structure of Fig. 1;

Fig. 3 is a view similar to Fig. l, but illustrating a modification;

Fig. 4 is a bottom end view of the structure of Fig. 3;

Figs. 5 and 6 are further vertical sectional views illustrating other embodiments; and

Fig. 7 is an exploded view in perspective illustrating parts of the internal structure of Fig. 6.

Briefly stated, my invention contemplates application to the construction of coils, transformers, chokes and the like for use in electronic circuit assemblies, as, for example, in the IF amplifier of a television set. The invention teaches integral formation 'of the turns or other internal parts of the circuit element component with the mounting leads or prongs, and for this purpose employs relatively heavy stiff wire for such parts. The assembly is .made rugged and adaptable to receive an adjustablypositioned magnetic core by securing the same in a cup-shaped plastic housing, closure being completed by acap, as upon permanent deformation of plastic parts QEQRQWWQBW 9m n; E oisa The present invention is concerned primarily with a basic structure applicable with equal facility to the construction of capacitor elements or resistor elements, alone or in combination with coil elements. In the case of capacitor and resistor applications, relatively heavy stiff wire is employed to form separate first and second electrical terminal members, each of which comprises a major fraction of a full turn thereof available for contact with a ring-shaped dielectric element or with a resist-anceelement, as the case may be. One end of each of these wires is bent and integrally formed to extend out the open end of the housing and to serve as the substantial.

. handling for automated assembly into a printed circuit.

Referring to Figs. 1 and 2 of the drawings, my invention is shown in application to a structural organization applicable with equal facility to the provision of a capacitance element or of a resistance element. The important parts of this element are received Within an annular space defined between inner and outer tubular parts 1112 of a cup-shaped housing 13, closed at 14 and open at the other end. Referring more particularly to Fig. 2, the important electrical parts of my new circuit element comprise first and second electrical terminal trode or contact parts are preferably flattened, as indicated at 17-18, so that contact with an intermediate dielectric or resistance material member 19 may be as extensive as possible. One end of each of the terminal members 1516 is integrally formed with a straight lead part 202 1, offset radially to avoid interference with other parts of the structure and extending substantially parallel to the central axis atangularly spaced locations. The lead parts 2021 project axially out and beyond the open end of the housing 13 and serve as mounting prongs and lead connections to thecircuit element.

The terminal members 1516 are formed from relatively heavy and stifi insulated wire, which may be heavy plastic-coated copper magnet wire or Copper- Weld (copper-sheathed steel wire). This wire is preferlably of a size and stiffness sufficiently rugged to permit projecting ends 20-41 to serve as the mounting pins for the finished structure so that no soldering or other connection to separate mounting pins is necessary to integrate the circuit component into its ultimate chassis.

For convenience in mounting, the leads 2021 may be nail pointed by employing conventional machinery, but I indicate my preference that the projecting ends 2021 shall be merely dipped in a pool of solder and slowly raised so as to develop pointed soldered ends 20'21' in the manner of a stalactite, the solder being further desirable for ultimate permanent assembly into a printed circuit. The leads 2021 may project for different axial lengths as shown, thereby providing unambiguous terminal identification.

For situations in which the circuit element of Figs. 1 and 2 is a capacitor, the annular member 19 interposed between the terminal members 15-16, consists of a mica, polystyrene or other suitable dielectric that has been conductively .coated on its opposed flat sides to achieve good carna e.- 9 .4. w s. wit he. tam n were Patented Feb. 21, 1961 -16 is-assured by strippingthe insulation from thecontact areas 17-18, and by tinning the same with solder.

For situations in which the circuit element of Figs. 1 and' 2 is'a resistor, the annular member 19-f is-of coiffse formed of" resistive material, andi tlie 'lead' ontermi'nal members 15-16"may*beatinnedas previously "indicated; The member 19 maybe a moldedf'element'of a plastic resistive "material, as; for 'example; an e'poxy-resin: binder premixed with carbon black. This composition ismolded' underheat and pressureto"obtainthe*size and shape illus'-' tratted, thereby achieving a rigidmechanical construction,

and in order to'obtai'n'igood electrical-contact to the ele ment 19, the opposite'faces thereof are suitablycoated with conductive material, as by the'silk-screening or evap orated-metal'processes indicated above-forzthe caseiof the capacitor.

It is sufiicient for most purposes that theterminal members 15-16 be held in'tight sandwichedrelation with the annular member 19 relied upon for the'desir'ed electrical performance, no soldering connection being necessaryto achieve such performance." In the particular arrangement shown, adequate axially retaining pressureis achievable by mounting the sandwich 15-19-16 between electrical-1y insulating spacer members'or collars 22-23, the inner collar 22 beingseated at the'bottom" of the space 10, and the outer collar 23 serving 'to provide'a seat for a closure-cap member 24. The cap member 24 happens to be shown also in Fig. 4 in connection with the structure of Fig. 3, but will be seen' to have a plurality of leadlocating recesses at angularly' spaced locations, the re c'esses 25-26 being. employed to locate leads 21-20. Permanent assembly is achieved by permanently deforming'abottom projecting end'27 of the inner'tubular portion-1-1 of the housing into radially overlapping relation with the closure cap 24. This operation is preferably performed under conditions of relatively strong axial pressure of the cap 24 against the bottom 14 of thehous- "1 This leav'e's'at" the closed end a substantially unwound portion into which a tuning, slug 34 of ferromagnetic materiatma'y' be receivedand axially adjusted? The" mere fact that this slug extends within'the'element15-19-16 in no way impairs electrical performance, andthe same T range of flexibilit y in' tuning adjustment for-the coil 30 is achieved, even for situations in which the element 15- 19-16 is a capacitor.

In the embodiment of Fig. 5, many of the parts of Fig. 3 will be recognized and have therefore been given the same reference'numerals. The e'mbodiment 'ofFig; 5

represents a multiple-elementcomponent wherein a coil' is in series with a resistor ora capacitor, depending upon' the nature of the element 19: In the structure of Fig. 5, the coil element 36* is again preferably of substantially lesser axial extent than the housing- 13, and is mounteding 13 so as to assure good, permanent-electrical cont-act desired, however, even more permanent relation of the partscan-be achieved if the spacer elements 22-23 are of aplastic material having a lower melting point than the material of the casing or housing 13, said-melting point being also lower than that" for the-element 19. Under such circumstances, transientlocalized'heating of the elements 15-16 will result inlocal melting of'adjacent-- parts of the spacers 22-23, and if this transient heating is properly timed (this being readily achievable when induction-heating techniques are employed), the parts may be fully consolidated to each other, the consolidated mass assuming some othercontour as suggested by-the dashed outline 28;-

In Fig. 3, I illustrate a further employment of the'principles of the invention, wherein a capacitor'element of the nature already described is combined with acoil element in a single housing 13. Because of the similarity of parts with those already identified, corresponding reference numerals are employed. The coil 30 may be of heavy stilt insulated wire (as used for elements 15-16 and may be of the type described in greater detailin said copending application; coil 30 is preferably of an axial length substantially less than the overall axial length of the housing 13, so asto permit axially spaced assembly of the elements 15-19-16 and of the coil 300d one of the tubular members 11-12 of the housing 13. In the form shown, both the elements 15-19-16 and'the coil 30are received upon and concentrically supported by'tlie inner tubular member 11, and their axially spaced rela: tion is determined by a spacer element or'collar 31". As explained in said cop'ending application, theends'*-ofthe coil 30 are bent axially at spaced 'lo'cations"and they m regrany form" mounting prongs and lead connections to near the open'end of the'same. 'Iheprincipal-difference in structure resides in the fact that the'axially inner end ofthe coil 36'is cut ofl- (and preferably'locally flattened,

as shown) at the last winding'tu'rn and is tinned for sub stantial peripheral contact with the adjacent coated surface of the annular member 19. If such member 19 is of dielectric material, then a capacitance is' formed between the axially'inner end-of coil'36 and the terminal member-15; which has already been described in connec-' tion with Figs. 1 and 2. It will be understood that in the situation depicted in Fig. 5, the axially inner end'of the coil 36 may be viewed as a terminal member, and the wirefrom which such terminal member is formed is in= tegrally formed at one end, namely, at'the axially outer end, with a straight axially projectingmounting-prong and lead structure 37 projecting beyond the open end and nevertheless integral with the coil 36;

In the form shown, a spacer 3 8 provides'a reference against which axial preloadingforces may be establishedupon securing'the cap 24, permanent deformation being achieved at a' bead or roll-over edge 27, as previously described. If desired, permanently bonded relation of the-parts may be achieved-by localized induction or other heating-so as to locally melt'a spacer 38 of relatively low melting plastic material, the ultimate bonded contour be ing somewhat of the shape indicated at 39.

The arrangement of Fig. 6 resembles that of-Fig. 5, except that each of the terminal members is formed as part of a" separate coil structure, there beingan inner coil 40 concentrically supported on the'inner tubular member 11 and an outer coil 41 deriving concentric support from the outer tubular member 12; The terminal member parts 40'41' for these coils are in substantially the same radial plane, and the element 19 of resistive'or dielectric material-is in radially overlapping relation with both-elements 40"-41'. If both sidesof the member 19 are conductively coated, as described in connection'with Figs. 1 and 2 '(the upper suface of member 19 being continuously conductively coated, and the lower surface being'coated over concentric but'radially spaced surfaces tact areas on the underside of member 19) should, of course, be substantially in excess of the effective axial thickness of the member 19, so as to assure that capacitance (or resistance) between 40'43 and 41-43 will dominate the electrical performance. As described in connection with the coil of Fig. 5, each of the other ends of the coils 40-41 is formed with an integral lead extending axially beyond the open end of the housing 13 and serving as a mounting support for the entire structure. -The lead to the inner coil 40 is shown at 44 and to the outer coil is shown at 45, both being located by cap 24. As previously indicated permanent bonding may be assured upon local melting of a low-melting spacer 46, as to an ultimate contour suggested at 47.

It will be seen that I have described improved circuit element constructions lending themselves to mass production and to extreme ruggedness of assembly. The structures are particularly useful for automated assembly into printed circuits, as by employing the same handling apparatus as used for coil structures disclosed in said copending application. Multiple components are achievable in the same structure, and by employing techniques as shown in Fig. 6, it is possible to double the inductance, while still combining circuit element properties with a resistor orwith a capacitor element 19. r I While the inventionhas been described in detail in connection with the preferred forms shown, it will be understood that modifications may be made Without departing from the scope of the invention as defined in the claims which follow.

. 1 claim:

1. In combination, a plastic cup-shaped housing comprising inner and outer tubular portions joined at one end to define an annular space open to the other end, a first electrical terminal member of relatively heavy and stiff wire and comprising at least a major fraction of a full turn thereof received within said space and deriving concentric support from one of said tubular members, a second electrical terminal member of relatively heavy and still? wire'and comprising at least a major fraction of a full turn thereof received within said space and deriving concentric support from one of said tubular members, an annular member of a material having electrical properties deriving concentric support. from one of said tubular members and in radially overlapping contacting relation with both said terminal members, one end of each of said wires including a straight integral lead portion extending out beyond the open end of said housing, and means fixedly holding said terminal members and said annular-member in said housing, the weight and stiffness of said wires being such that said projecting wire ends provide the substantial mounting support for said combination.

2. Thecombination of claim 1, in which said annularmember is of a dielectric material.

3.1The combination of claim 1, in which said annular member is of a resistance material, the resistance being substantially in excess of the resistance of said terminal members.

' 4. The combination of claim 1, in which the turns of said terminal members are flattened at the area of contact with said annular member.

5. In combination, a plastic cup-shaped housing comprising inner and outer tubular portions joined at one end to define an annular space open to the other end, a first electrical terminal member of relatively heavy and stifi wire and comprising at least a major fraction of a full turn thereof received within said space and deriving concentric support from one of said tubular members, a second electrical terminal member of-relatively heavy and stifl wire and comprising at least a major fraction of a full turnthereof received within said space and deriving concentric support from the said one of said tubular mem- Psr sai s t tisa ms bw being ia y 9P 9 a r jacent relation, an annular member of a material havingv electrical properties deriving concentric support from said one tubular member and interposed between said terminal-member turns and of a radial extent to radially overlap and contact both said terminal members, one end of each of said wires including a straight integral lead portion extending out beyond the open end of said housing, and means fixedly holding said terminal members and said annular member in said housing, the weight and stiffness of said wire being such that said projecting wire ends provide the substantial mounting support for said combination.

6. In combination, a plastic cup-shaped housing comprising inner and outer tubular portions joined at one end to define an annular space open to the other end, a first electrical terminal member of relatively heavy and stiff wire and comprising at least a major fraction of a full turn thereof received within said space and deriving concentric support from one of said tubular members, a second electrical terminal member of relatively heavy and stifi? wire and comprising at least a major fraction of a full turn thereof received within said space and deriving concentric support from the other of said tubular members, both said turns being in substantially the same radial plane, an annular member of a material having electrical properties deriving concentric support from one of said tubular members and in radially overlapping contacting relation with both said terminal members, one end of each of said wires including a straight integral lead portion extending out beyond the open end of said hous-' ing, and means fixedly holding said terminal members and said annular member in said housing, the weight and stiffness of said wires being such that said projecting wire ends provide the substantial mounting support for said combination.

7. In combination, a plastic, cup-shaped housing comprising inner and outer tubular portions joined at one end to define an annular space open to the other end, a first electrical terminal member of relatively heavy and stifl! wire and comprising at least a major fraction of a full turn thereof received within said space and deriving concentric support from one of said tubular members, a second electrical terminal member of relatively heavy and stiff wire and comprising at least amajor fraction of a full turn thereof received within said space and deriving concentric support from the other of said tubular members, both said turns being in substantially the same radial plane, an annular dielectric member deriving concentric support from one of said tubular members and in radially overlapping contacting relation with both said terminal members, one end of each of said wires including a straight integral lead portion extending out beyond the open end of said housing, and means fixedly holding said terminal members and said annular member in said housing, the weight and stiffness of said wires being such thatsaid projecting wire ends provide the substantial mounting support for said combination.

8. In combination, a plastic, cup-shaped housing comprising inner and outer tubular portions joined at one end to define an annular space open to the other end, a first electrical terminal member of relatively heavy and stiff wire and comprising at least a major fraction of a full turn thereof received within said space and deriving concentric support from one of said tubular members, a second electrical terminal member of relatively heavy and stiff wire and comprising at least a major fraction of a full turn thereof received within said space and deriving concentric support from the other of said tubular mem bers, both said turns being in substantially the same radial plane, an annular electrically resistive member deriving concentricsupport from one of said tubular members and in radially overlapping contacting relation with both said terminal members one end of each of said wires includinga straight integral lead portion extendingout 7 Beytinu t-heopenend o'f'said housing," and means fiir'edly lidlding' saidterminal members and said annular member in s aid housing; tli'eQw'eight and stilfness of said wires" beingsuch that saidprojecting Wire ends' provide the substantial mounting supportfor said combination.

9. In combination, a plastic cup-shaped housingcom prising-inner" and outer tubular portions joined at one end-to define anannular space open to the other end; a" first electrical terminal member of relatively heavy and stiff wire and comprising at least a major fraction of a full turn thereof received within said space and deriving concentric support from one of said tubular members, a second electricalte'rminal member comprising a coil having a-numberof turns of relatively heavy and stilt wire received within said space and deriving concentric support from one of said tubular members, an annular member of a material having" electrical properties deriving concentricsupport from one of said tubular members and in radially overlapping contacting'relation with one axial end of each of said terminal members, one end of the wire of'said first terminal member including a'straight in-' tegral lead portion extending out the open 'end of said housing, and the other end of thewire of said coil in-' cluding a straight integral lead portion angularly spaced from said first lead portion and extending out beyond the open end-of said housing, andmeans fixedly holding'said terniinal members and said annular member in said'hous'-" ing, the-weight and stiffness of'said wiresbeing' such that said projecting wire ends provide the substantial mount ing support for said combination.

10. In combination, a plastic cup-shaped ho'usingcorn prising inner and outer tubular portions joined "atone' end'to define an'annular space open to the othejrfend, a first electrical terminal member comprising acoil of rela tively heavy and stiff wire received within saidspaceand deriving concentric support from one of said tubular members,-a-second electrical terminal member comprising-acoil of'relatively heavy and stiff wire received 'with in said space'and deriving concentric support fromone of said tubular members, an annular member of a material having electrical pro'pertiesderiving concentric support frorn one of said tubulanmembers and in radially over lapping contacting relation with one end of each of said terminal members,'the other end of each of said terminal members including a straight integral lead portion extend ing out'beyond the open end of said housing, and means fixedly'holding said terminal members and said annular member in said housing, the weight and stifiness'of said Wires being such that said projecting wire endsprovide the substantial mounting'support for said combination.

11. The combination ofclaim' 10, in which said coils are coaxial. l I

12. The 'com bination of claim 10', in which one ofsaid" coils-derives concentric support from one of saidtubhla'rportions, and the other'of said coils derives concentric support from the other of'said tubular portions.

13. The combination of claimflO, in which said cdils arecoaxially supported withinsaid space, the axially/ inner ends of said coils being in substantially the same radial plane, said annular member comprising an electrically conductive layer and dielectric means interposed betweensaid layer and the adjacent endsof said coil.

14. 'In'combinatiom-a plastic cup-shaped housingcdriiprising inner and outer tubular portions joined at one end to define anannular space open 'to the other end, a first electrical terminal memberof relatively heavy and stiff Wire and comprising-at -least substantially a full-turn thereofreceivedf within said spaceand deriving concentric support fromthe inner" of' said' tubular members, a second: electricalterminal'niember of relatively heavy and 1 stiff wire and comprising substantially' a full turn thereof received within-said space and deriving concen' tric support from said-inner' tubular mernb'e mammal electrically resistive member deriving concentric" support prising inner and outer tubular portions joined at one tric support from the inner of said tubular members, a

from s'aid infne'r tubular member and axially interposed between said electrical terminal members, abutment means within said space and defining an inner insertion" limit for'the axially innerone of said terminal members,-

- and closuremeans for'the open endof saidhousingand T of said housing, the weight and stifiness of said wires being such that said projecting wire ends provide the substantialmounting' support for said combination.-

15. In combination, a plastic cup-shaped housing-corn end to define an annular space open to the'other end, a first electrical terminal member of relatively heavy stitf wire and comprising at least substantially a full turn thereof received within said space andderivingconcen second electrical" terminal member'of relatively heavy and'stiff wire and comprising substantially a-full' turn thereof received within said space and deriving'concen tric support from said inner tubular member, anfannulan dielectric member deriving concentric support from said inner tubular member and axially interposed between said electrical terminal members, abutment means within permanent relation, one end of each of said wires including a straight integralleadportionextending through said closure'rneans and out beyond the open-end offsaid housing, the weight and stiffness of said wires being" such" that said projecting wire endsprovide the substantial mounting support for said combination;

16': In combination, a plastic cup shaped housing comprising inner and outer tubular portions joined at one end to define an annular space open to the other end,

a first electrical terminal'member of'relatively heavy stiif wire and comprising a'tleast substantially a full turn thereof received within said space and 'deriving'concentrio-support from the inner' of said tubular members, a second electrical terminal member of relatively, heavy and stiff wire' andcomprising substantially a'full' turn thereof received withinsaid space and deriving concentric support from saidinner' tubular member, an annular member'of' a material havingelectrical properties derivingrconcentric-support from said inner tubular member and-in radially overlapping contacting relation with both said terminalmember's and axially interposedtherebetween; said terminal members beingdis'posed at the axially inner part of said space, a winding of relatively heavy and stifi'wire of leses'r axial extent than the depth of said space and of relativelyheavy" an'dstifi 'wire deriving concenfricsupport from said-inner tubular member nearthe' open end thereof, spacer means of insulating mater-iazlaxially: separating said terminal members from said coil, one end of each of the wires" of said terminal membersand both ends of said'coil including straight integral lead portions angularly' spa'ced-withre spect to each other and extending outbeyond the open end ofsaid housing, andmeans fixedly holding said ter minal members and said annular memberin said housing,- the weight and stitfness'of said wires-being such thatsaid projecting wire 'ends 'provide the substantial mounting support for said combination. g h

17. The combination ofclai m; 16 and including a core member 'orferroma'gnetia material adjustably receivedin the bore'ofsaid i'nner'tubularpontion.

18; In combination, a plastic cup-shaped housing, compri'singinner and outer tubular portions joined at one end to"definean annular space open to th'e other end, a first electrical" terminal memberof relatively heavy and stiff" wire and comprising'substantially a full turn thereof received within said space and deriving concentric support from the inner of said tubular members, a second electrical terminal member of relatively heavy and stifl. wire and comprising a multi-turn coil received within said space and deriving concentric support from said inner tubular member, said coil being of axial extent substantially less than the axial extent of said housing and being received on said inner tubular member near the open end of said housing, an annular member of a material having electrical properties deriving concentric support from said inner tubular member and axially interposed between said terminal members, means axially securing said terminal members in permanent sandwiched relation with respect to said annular member, one end of each of said wires including the straight integral lead portion extending out beyond the open end of said housing, the weight and stiffness of said wires being such that said projecting wire ends provide the substantial mounting support for said combination.

19. The combination of claim 18 and including a core element of ferromagnetic material adjustably received in the bore of said inner tubular member near the closed end of said container.

20. In combination, a plastic cup-shaped housing comprising inner and outer tubular portions joined at one end to define an annular space open to the other end, a first electrical terminal member of relatively heavy and stiff wire and comprising a multi-turn coil received within said space and deriving concentric support from one of said tubular members, a second electrical terminal member of relatively heavy and stiff wire and comprising a multi-turn coil received within said space and deriving concentric support from the other of said tubular members, both said coils being of axial length substantially less than the axial extent of said housing and both said coils being supported near the open end of said housing with the axially inner limits of said coils in substantially the same radial plane, whereby a substantial unwound axial length of said housing is defined at the inner end thereof, a dielectric washer radially overlapping both inner ends of said coils and in contact therewith, an electrically conductive layer axially inward of said dielectric washer and in radially overlapping relation with the inner ends of both coils, means fixedly holding said conductive layer in compressed relation against the inner ends of said coils via said dielectric washer, the weight and stifiness of said wires being such that said projecting wire ends provide the substantial mounting support for said combination, the axially outer end of each said coil including a straight integral lead portion extending out the open end of said housing.

21. The combination of claim 20, and including a core member of ferromagnetic material adjustably received in the bore of said inner tubular member near the closed end of said housing.

No references cited. 

